nub question, yet hope ull answer

I have started mining for the first time, seems right.
I chose ETC to start, with a single msi 7970 twin frozr and get
12.1 m/h.Is this ok or should i tweak it?
I got another r9 280 and will point it also at it, but thats for later :X
Thanks!
Get 50+ more gpus or its really not worth it.
Now you make what? 0,5 $ a day?
Edit:
Investing in new gpus today is risky, as ROI has been crashing hard. You might even not hit green ever if you invest in gpus today.